here is a new proposal for colorramp UI.
Testing this code, the large color band (as in the blender material properties for example) looks inconsistent now.
I think that one should use the same icons, and move the button to chose the color stop below the color band, to the left of the position button, so you get the stop, position and color on the same line (which should be ok here as the editor is assumed to be wider).
by any chance could each color stop added have an input for it's value and position exposed? (so i could control the position with a bw image, and for intance plug a texture to one of the colors), that would make it even more useful!